n] (,'cntni/ Itcimn-kx on Tr/vv Cell Laniiiidtioii 17 



sections ot the calcarine cortex stained for nerve cells be superimposed on ones stained for 

 fibres, tin 1 main hulk of the Haillargie line will be seen lying above the stellate cell 

 collection; and in other regions of the brain, a faint, pallid zone, situated immediately below 

 the line of Haillarger, usually diMiot.es the position of this lamina. Furthermore, a redupli- 

 cated line of Baillarger is not the outcome of a reduplicated stellate layer. 



1 uti i-iHil Layer of Large Pyramidal Cells. 



Sometimes called the " ganglionic " layer, this is another lamina which will claim a 

 large share of interest in later chapters, for its constituents are the subject of most profound 

 and interesting changes in different cortical territories. In fact it seems that these cells 

 play a direct role in both motor and sensory functions, that they are capable of serving 

 either as projecting stations for efferent impulses, or as receptacles for incoming stimuli. 

 And although I cannot enter into the question here, it is reasonably maintained by some, 

 that the giant cells in the motor area are the homologues of the "solitary" cells in the 

 visual area ; and the homology is capable of extension. The absence or relatively feeble 

 development of these elements in "silent" unknown fields is significant in this connection. 

 It must be mentioned that this lamina is never pure in constitution, it is contaminated by 

 cells of varied shape and size. Its constituents undoubtedly bear a direct relation to the 

 fibre wealth in the radiary zone. 



Layer of Spindle-Shaped or Fusiform Cells. 



The last and lowermost layer is soon dismissed. The shape of its cells is well-expressed 

 by the title. It seems to be a fundamental layer, is represented over the entire cerebrum 

 and does not show pronounced topical differences. As others have pointed out, on the 

 walls and floor of sulci, these cells come to lie with their long axis parallel with instead of 

 at right angles to the surface. Nestling among the radiations of Meynert, a columnar arrange- 

 ment is commonly forced upon them. 



It might be finally pointed out that, if the depth and general appearances of these 

 combined strata be inspected, first on the wall, [then on the lip, and finally on the crown, 

 in a section of any individual gyrus, variations will be observed, attributable to influences 

 of compression or expansion in the process of cerebral development, and so, in comparing 

 the cell structure of different gyri or parts, it is essential to confine attention to corre- 

 sponding sectional parts. 



REFERENCES. 



ADOLF PASSOW. Ueber den Markfasergehalt der Centralwindungen eines normalen mannlichen 

 Individuums. Neurolog. Ceittralb., No. 6, 1898. 



OSCAR VULPIUS. Ueber die Entwicklung und Ausbreitung der Tangentialfasern in der menschlichen 

 Grosshirnrinde wahrend verschiedener Altersperioden. Arch. f. Psycli. u. Nervenkr., Bd xxm, Heft 3, 

 1892. 



TH. MEYNERT. Der Bau der Grosshirnrinde und seine ortlichen Verschiedenheiten nebst einem 

 pathologisch-anatomischen Corollariuni. Virrteljahrschr. J. Psych., 1872. 



c. 3 



